Peugeot 406 - Immobilizer light on, car fails to start

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Wed 9 Apr 2014 01:41
Peugeot 406 - Immobilizer light on, car fails to start - notanother406

Drove my car the night before ok and in the morning the Immobilizer light was on with the dashboard road lights indicator flashing constantly and the wipers being active. I can hear the fuel pump priming, the engine turns over but it won't start because the injectors are disabled by the ecu.
I have replaced the complete set of identical ECU, BSI unit and lock and key with transponder and no joy, exactly the same symptoms.
ECU diagnostics check suggested the Comm 2000 unit could be at fault. I have changed this too but no change.
Fuses had been checked and ok. What is puzzling is the blinking of dashboard road light indicator and wipers moving which I cannot stop and when I put the ignition on, the immobilizer light is on.
Any ideas anyone? Everyone else advised me to ditch the old lady...shame as it is mechanically sound.
Thanks
Dan

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Wed 9 Apr 2014 14:55
Peugeot 406 - Immobilizer light on, car fails to start - Gibbo_Wirral

You're on the right lines with the COMM2000 unit being faulty. However, how old is your battery and have you had the battery off and not performed a BSI reset?

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Wed 9 Apr 2014 23:49
Peugeot 406 - Immobilizer light on, car fails to start - notanother406

hi gibbo-wirral, thanks for your reply.

The battery is brand new with plenty of amps on it.

On the bsi reset, i have followed the procedure but i cannot hold the fob close button held for the required 10 sec as the button on the electronic board is broken. is this mandatory?

There seem to be wet in the rear footwell from the heavy rain, are there any connectors under the carpets somewhere?

I think i have exhausted every avenue, apart from paying good money after bad,,,

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Wed 9 Apr 2014 23:53
Peugeot 406 - Immobilizer light on, car fails to start - elekie&a/c doctor

Have you checked the battery and chassis earth points?.Most peugeots seem to have a main connection point on top of the gearbox.

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Thu 10 Apr 2014 14:39
Peugeot 406 - Immobilizer light on, car fails to start - Gibbo_Wirral

You've hit the nail on the head with the water in the footwell. Water ingress is the problem. Have a look in the 406 section of peugeotforums.com, plenty of reports of this and recommendations.

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Sat 12 Apr 2014 01:23
Peugeot 406 - Immobilizer light on, car fails to start - notanother406

thank you for your help.

i believe the problem lies with connectors underneath the driver side carpet.

water got inside footwell and rotted connectors.

why on earth would they design somethink so bonkers???

thanks peugeot, great engines but leave the electrics to some that use common sense...

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